The report is by the Civil Rights Project at the University of California at Los Angeles. It looks at enrollment trends from 1989 to 2010 in New York state and in New York City, the largest school system in the U.S. with 1.1 million pupils.

The study's authors say segregation has the effect of concentrating black and Latino students in schools with high ratios of poor students.

The study suggests that New York's segregation is largely due to housing patterns but that it could be mitigated through policies intended to promote diversity.

Other states with highly segregated schools include Illinois, Michigan and California, according to the Civil Rights Project.